The unexpected bear behavior was dismissed as folklore in the past although there is certainly evidence of other life forms using rocks as tools:
At one time, researchers thought it was a myth that polar bears could use stones to kill walruses. Not any more:
“Walruses, weighing as much as 1,300 kilograms with huge tusks and nearly impenetrable skulls, are almost impossible for a hungry polar bear to kill. But new research suggests that some polar bears have invented a work-around — bashing walruses on the head with a block of stone or ice.
For more than 200 years, Inuit in Greenland and the eastern Canadian Arctic have told stories of polar bears (Ursus maritimus) using such tools to aid in killing walruses. Yet explorers, naturalists and writers often dismissed such accounts, relegating them to myth along with tales about shape-shifting bears. – Gloria Dickie, “Polar Bears Sometimes Bludgeon Walruses to Death with Stones or Ice” at Sciencenews (July 29, 2021). The Paper Is Closed Access.” News, “Polar bears use stones to kill walruses” at Mind Matters News
Here’s a video of a polar bear throwing a block of ice at a seal (the camera was attached to the bear; hence the bumpiness):
Takehome: The life forms that use rocks and stones as tools are reversing a process: bringing the rock to smash prey instead of bringing prey to be smashed on the rock.
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